Sacked NBN Co director Brad Orgill has slammed interference in the national broadband network from both sides of politics, claiming the rollout was dysfunctional under Labor and lashing new minister Malcolm Turnbull over his purge of the board.

Mr Orgill said that when he joined the board in September 2012 parts of NBN Co were dysfunctional and that delays in the rollout were unacceptable.

Mr Orgill was the only director who refused to voluntarily resign from the board last week.

“I chose not to resign with all other board members . . . [because of] my weariness at politics overshadowing fair process," he said in an exclusive opinion piece in Friday’s Australian Financial Review. “That [Mr Turnbull] declined to even meet with the board before demanding all to resign was disappointing."

As first flagged by the Financial Review, the Coalition has appointed former Telstra and Optus chief executive Ziggy Switkowski as executive chairman of NBN Co. Mr Turnbull also retained existing directors Kerry Schott and Alison Lansley, who joined the board last year, for “continuity".

Ms Schott previously worked at Mr Turnbull’s investment bank Whitlam Turnbull while Ms Lansley conducted work on all three stages of Telstra’s privatisation while at Mallesons Stephen Jacques.

The three executives will act as a quorum, which is the minimum number of directors needed to keep the company running. Dr Switkowski, who most recently held non-executive directorships at Suncorp and Tabcorp, will lead the $20.4 billion project until a permanent chief executive is appointed.

“Dr Switkowski has had a lot of ­experience in the telecom sector and elsewhere in the business world and we have every confidence in him," Mr Turnbull said. “The reception to his mooted appointment . . . has been very positive."

“Dr Switkowski has not been hired or been appointed here as somebody to be the head of construction," he said.

“The previous communications minister but one, Mr Stephen Conroy, regarded technology as an ideological political issue and that’s why billions of dollars have been wasted. The bottom line is you use whatever technologies will deliver that outcome most ­effectively."

Mr Orgill claimed Mr Turnbull’s decision to sack him from the board on Thursday was directly related to his role investigating Labor’s Building the Education Revolution (BER) Program.

In an apparent swipe at Senator ­Conroy, Mr Orgill said NBN Co was in a bad state when he joined the board and that the construction delays were “unacceptable".

“Has there been political involvement in operations? Yes," he said.

“I was struck by the dysfunctional nature of various NBN operational aspects but also impressed by what had been achieved in many of the workstreams," he said. “We could have got the local network component back on track to complete as scheduled by 2021."

He also said that while Labor should have subjected the NBN to a ­cost-benefit analysts the whole project would not have been required if the Coalition had not sold Telstra as a vertically integrated telco.

Mr Turnbull could have taken control of the board without sacking anyone, but decided to do so anyway, Mr Orgill said.

The first task of the NBN Co board will be a 60-day strategic review of the current state of the network rollout, its financial viability and potential savings measures to bring the cost of the NBN to the Coalition’s preferred figure of $20.4 billion.

The review is likely to consider the extent to which the rollout will move from a wholly fibre-optic network to most of the population, to greater use of Telstra’s existing copper network.

The board will also formalise a timetable for detailed negotiations with ­Telstra. The $11.2 billion deal, which took more than two years to negotiate, gives NBN Co rental access to the huge network of underground pits and ducts that contain Telstra’s phone network.

The Coalition government will now need to buy and use Telstra’s copper network, once valued at up to $17 billion, to build its fibre-to-the-node ­system, in a set of negotiations NBN Co has previously warned would be more complex and risky than the existing deal. However, outgoing NBN Co chief executive Mike Quigley told staff in an email on Thursday that adding fibre-to-the-node technology as an option would “allow the NBN to be built more quickly and at less cost to the taxpayer".

He said the company was in good hands under Dr Switkowski. “We have known one another for a good many years and you can be assured that with Ziggy at the helm NBN Co will be in good hands as the company makes the transition to meet the objectives set by the new government. It has been a pleasure and a privilege to have led NBN Co [and] you can all feel proud of what you have achieved in that time."

Telstra and Optus executives also welcomed Dr Switkowski’s appointment, while former colleagues have praised him for his experience.

“He will be quite capable of unpicking it very effectively and putting it together in a way that maximises value for taxpayers and shareholders," said former Liberal communications minister Helen Coonan, who is also believed to have been approached for a ­non-executive directorship at NBN Co.

But Shadow Communications Minister Anthony Albanese hit out at the change within hours of the announcement, saying Dr Switkowski had never been in charge of any major network construction activity during his time at Optus and Telstra. “[Dr Switkowski’s] tenure at Optus and Telstra was not without controversy," Mr Albanese said. “Before the election, Mr Turnbull claimed he would add experience relevant to the NBN rollout, but he has failed to do so.

“Mr Turnbull’s record as a Minister and Opposition Leader shows he has a tendency to be impetuous."

In a 2009 interview, Dr Switkowski said he believed the NBN was an important project and that “an all-fibre ­network is a desirable endpoint".

“I think the government strategy of investing in a high-speed fibre-optic base broadband network is a good one," he said at the time. “I think it will make a difference to us as a nation and it will ensure more equity in access to relevant services for all Australians.

“I think the best solution would see Telstra at the heart of such a network and that the network ideally would be made up of the components that ­currently are owned by the telecom companies, predominantly the biggest being Telstra, and then extended where coverage doesn’t currently exist."